Extrusion of camphor and product thereof



.1 QFFICE UNHTE!) SITES EXTRUSION OF GAMPHOR AND PRODUCT THEREOF Ivan Gubelmann, Wilmington, Dcl., and William S. Calcott, Woodstown, N. 3., assignors to E. I. du Pont de Nemours & Company, Wilmington, Del, a corporation of Delaware No Drawing. Application December 8, 1936,

Serial No. 114,862

3 Claims. (01. 1848) This invention relates to shaped solid camphor, forced through the opening in a rod form and more particularly it relates to shaped camphor may have an indeterminate length. It is transhaving an indeterminate length and a small cross lucent. If instead of a round die, the opening is section, still more particularly it relates to camin the form of a rectangle, the solid camphor is 5 phor in the form of rods, bars, tubes, ribbons, secured in the form of a ribbon or astrip. 5

sheets, etc., of small cross section, and still more Example H particularly it refers to a process which comprises forcing camphor through a restricted opening.

This invention has for an object the production Liquid camphor having a melting range of 160-164= C. is placed in a 2" x 15" cylinder. It of new shaped forms of camphor. A further obiS wed to 0001 to 140 C., after which it is 10 ject is the preparation of solid camphor in shaped forced through an Opening in diameterforms which have commercial utility. A still Camphor in foil form is Securedfurther object is the production of solid camphor Example I In shaped forms of small cross section and indeterminate length in commercial quantities,and in f f f haVIFg a fe g of 15 general an advancement of the art. Other ob- 160 i Placed m 2 X 15 P The cylmder 1s heated to 150 C. for a perlod of J'ects will appear hereinafter.

These objects are accomplished the followfOul hours. The Camphor 15 then forced through ing invention which comprises forcing camphor an Opening in diameter- Camphor; in

20 in a plastic state through a restricted opening. form is Secured- 20 This may be done in everal Ways the In the preferred. embodiment Of the present Inconventional die extrusion apparatus and technic Vention, liquid- Camphoi is continually cooledto for plastic materials after the camphor is COD- a plastic State and When State is attained verted into a. suitable state. The extrusion of is continuously forcedthrough a restricted- Open the camphor may be carried out in the absence a of free oxygen. It is possible to start with crystalhne camphor Thus, the Objects may be accomplished by and heat it to the temperature required for continually feeding liquid camphor into an appaverting it into a plastic state. The temperature ratus which is capable of gradually cooling the and time of heating are determined P the quality material and, at the same time, forcing it through of camphor f the y of eqmpment used- 30 a restricted opening. It is essential that the Camphor havl ng a meltmg range of 17404770 camphor be in a plastic state while and preferbecomes plasiuiwhen 1 from 50 i ably b f r it passes through the opening The perature below 1ts melting point. Appllcation of temperature, f example, may range fr m about forces which cause the camphor to flow facilitates 50 0. to about 170 c., and preferably from the development o p ast c ty. 35 70 C. to 150 C. The terms plastic and plastic state are 1n- The objects may be accomplished also by grad tended to connote that the camphor is in a homoually heating solid camphor until it becomes plasgeneous Condition and can be bent molded tic is heating until a temperature of Shapes disturbing transparency.

40 between about 50 c. and about 170 0., and Camphor in a non-plastic state crumbles d ly. 40 preferably about 70 C. to about 150 C., is s granular 0r pulv it y be y t reached. The plastic state can be obtained by a carefully The invention will be further illustrated, but Controlled regulation of p u The is not intended to be limited by the following ex- Derature required depends p the q y o amp1es the camphor started with as well as its physical 45 state (viz., liquid, solid, crystalline). The temperature may range from slightly below its melt- Liquid camphor having a melting range of 175 ing point to about C. In the case of liquid C. to 177 C. is fed continually into a machine in camphor of a melting point between l75-1'77 C.,

50 which it is gradually cooled and at the same time a temperature between 70-1'70 C. gives excellent 50 pushed forward, forcing this camphor which is results and a temperature between 70-150 C. in the plastic state through a restricted opening Camphor having a lower melting range (for exmeasuring in diameter. As the plastic camample, 160-164 C.) is extruded at a temperaphor reaches the restricted opening, its temperature between 50 and 150 C., and preferably at ture ranges from -170 C. The material is about C. 55

Example I type press or extruding machine may be used quite satisfactorily. The screw may be one of many types, such as a variable pitch screw or a tapered screw, and may be jacketed with water, steam or oil, or other media for better temperature control.

Cold crystalline camphor can be forced through a restricted opening provided excessive pressure is used. The pressure required is about 8000 pounds per square inch. As soon as the camphor leaves the opening, it tends to split in different directions. 7 I

When camphor in a plastic state is forced through a restricted opening, the pressure required is much less and the material is translucent. Shaped products of indeterminate length may be obtained.

This invention has the advantage that camphor may be easily prepared in a commercially desirable form which is transparent to opaque.

' It will be apparent to those skilled in the art that many different embodiments of the invention may be made without departing from the extruding the camphor while it is in a plastic state through a restricted opening.

2. The process for producing transparent camphor which comprises cooling hot liquid camphor until itreaches a plastic state and continuously extruding the same while it is in a plastic state and at a temperature from about 50 C. to a temperature slightly below its melting point through a restricted opening to form a strip of camphor.

3. The process for producing transparent camphor which comprises cooling hot liquid camphor until it reaches a plastic state and continuously extruding the camphor While it is in a plastic state and at a temperature from about 50 C. to a temperature slightly below its melting point and under a pressure between about 50 and about 500 pounds per square inch throughout a restricted opening.

IVAN GUBELMANN. WILLIAM S. CALCOTT. 

